Silicated flue-dust.



UNITED STATES PATENT OFFICE.

EDWARD H. WILLIAMS, OF SHARON, PENNSYLVANIA.

SILICATEDIFLUE-DUST.

SPECIFICATION formingpart of Letters Patent N 0. 723,106, dated March 17, 1903.

Application filed October 24, 1901.

To all whom it may concern:

Be it known that I, EDWARD H. WILLIAMS, a citizen of the United States, residing at Sharon, in thecounty of Mercer and State of Pennsylvania, have invented a certain new and useful Improvement in Agglomerated Iron Ore for Smelting, of Which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

In the reduction of certain iron ores, notably those from theMassaha range, in a blastfurnace a fine impalpable powder, known as flue-dust, is developed and is carried off by the draft of waste gases. Thoughthis powder is rich in iron, being in the instance of a Massaba ore a ferric oxid, (F it is so very impalpable that it has not been, so far as I am aware, heretofore utilized to any material extent, being simply added to the dump, for if it be reintroduced into the furnace it is simply blown out again by the blast. I have discovered that if this powder be fused with a small percentage of silica (SiO,) the silica is converted into a ferrous silicate, and this binds the remaining oxid into a slag, which can be very conveniently utilized in the blast furnace. The amount of silica which should be added in making my proposed slag varies with circumstances. I have found seven per cent. to be satisfactory,

though this silica may vary from two per Serial No. 79,885. (No specimens.)

not itself take into the product unsatisfactory ingredients, such as would be contained in refuse slag, 650.

An efficient method of making my composition of matter is by the process which is the subject of my copending application, Serial No. 44,363, filed January 23, 1901, entitled Process of reclaiming flue-dust. In such process I fuse the flue-dust and the silica by feeding them both under the surface of a molten bath of iron oxid and iron silicate contained in a reverberatory furnace, the heat being applied to the surface of the bath and the resultant slag being drawn 01f as the process continues.

I am aware that there have been various slags and cinders which contained iron oxid and ferrous silicate; but such slags do not have the small per cent. of silica which my invention calls for nor do they have these ingredients alone, but have so much silica and other ingredients as not to be utilizable in the furnace.

I claim-- 1. A composition of matter consisting of uncombined iron oxid and iron silicate free from impurities.

2. A composition of matter consisting of uncombined iron oxid, together witha small percentage of substantially pure iron silicate binding the oxid into a slag.

3. A composition of matter consisting of uncombined iron oxid, together with a small proportion of iron silicate derived from free sand, binding the oxid into a slag.

In testimony whereof I hereunto affix my signature in the presence of two witnesses.

E. H. WILLIAMS.

Witnesses:

DAVID KENNEDY, PAUL D. FARRELL. 

